Contact lenses provide a means for vision correction for a wide range of consumers. The advantages of contact lens wear are numerous. Improved convenience and improved appearance in comparison to spectacle glasses are probably the two most important advantages to most consumers. However, contact lenses require stringent care regimes in order to ensure comfort and avoid ocular infections. Proper care of contact lenses typically requires the consumer to periodically clean, disinfect, and/or rinse the lenses. Cleaning usually refers to removal of lipids, proteins or other matter which has become affixed to a lens. Disinfecting usually refers to inactivating of harmful bacteria or fungi whenever the lenses are removed from the eye, which is usually on a daily basis. Rinsing usually refers to removing debris from the lens before placing the lens in the eye.
Traditionally, disinfecting, cleaning and/or rinsing of lenses are not carried out in the eye but occur at the end of day (e.g., in the evening) by immersing a lens in an appropriate lens care solution (for example, a single- or multiple-purpose care solution) in a contact lens case. Such lens cases can be used to store contact lenses between use periods. When it is desired to treat contact lenses, the appropriate contact lens care composition is removed or dispensed from a bottle or container including the composition and passed into the contact lens case in which the contact lenses have been placed. Contact lenses are often left in the lens care solution in the lens case for an extended time, for example, overnight or at least several hours. After treatment, the contact lenses are ready for wear in the eyes of an user. In general, lens care requires the user first taking out of the lenses and then clean, disinfect, and/or rinse them.
But, users may occasionally want to clean and lubricate lenses during the day. Such occasional lens care during the day may be inconvenient for an user since the user needs to take the lenses out of the eyes and then reinsert them into the eyes after cleaning and lubricating.
In addition, a new class of high Dk soft contact lenses, which are made from high oxygen permeable silicone hydrogel materials, have been developed and are commercially available. Such soft contact lenses allow sufficient oxygen to permeate through the lens to the cornea and can have minimal adverse effects on corneal health. This new class of high Dk soft contact lenses can be worn in one of two wearing modalities: daily wear and extended wear (i.e., worn overnight and even continuously over a plurality of days, e.g., up to 30 days). With the advent of extended wear modality, conventional lens care regime and conventional lens care solutions can no longer be used to clean and lubricate lenses while worn in the eye.
It would be desirable to directly clean and lubricate the lenses in the eyes (i.e., without taking out of the lenses from the eyes). Therefore, there exists a need for a lens care solution capable of cleaning and lubricating the contact lens directly in an eye. It is to the provision of a lens care product meeting these and other needs that the present invention is primarily directed.